Typically, when a fully automatic firearm is cocked, the breech travels toward the rear of the firearm and is there secured (e.g., locked) in a rear locking or latching position against a spring force of one or more closing springs. The firearm may be cocked manually. When a trigger of the firearm is actuated, a locking mechanism is released and the one or more closing springs move the breech in a breech path toward a front of the firearm. The movement of the breech causes a cartridge to be inserted into the breech path, locked in a cartridge chamber toward a front end of the breech path and thereafter ignited. After the breech is released, gas pressure or recoil created by the cartridge ignition moves the breech toward the rear of the firearm into the rear locking position and the empty cartridge casing is ejected. Cartridges may be fed into and/or ejected from the firearm via the movement of the breech and/or the gas pressure or recoil created by the cartridge ignition, for example.
Safety devices (e.g., firearm safeties) may be used that prevent the breech of a cocked firearm from being released and, thus, unintentionally firing a round. Some safety devices may be moved (e.g., mechanically moved) behind the trigger of the firearm. Other safety devices may secure the breech in the rear locking position. Because of the relationship between the safety device and the trigger, in some firearms, the trigger may only be retracted if the breech is in the rear locking position. In other firearms, the relationship between the safety device and the trigger substantially prevents the safety from being engaged (e.g., intentionally engaged) when the firearm is firing because the safety blocks the safety catch and keeps the trigger in the shooting position. Because the breech is thus not secured in the rear locking position, the one or more closing springs move the breech again toward the front of the firearm to begin the next firing cycle. Engaging the safety when the firearm is firing may cause the firearm to continuously fire even if the trigger is disengaged, for example.
Additional issues may arise in fully automated weapons that have remotely controlled safety devices. While these weapons are firing the safety device may activate because of a malfunction, such as a cable breaking or power failure. However, after a malfunction, the safety device may be actuated into position prior to the breech being in the rear locking position even if the trigger has been released because the breech takes a particular amount of time to reach the rear locking position. The particular amount of time that the breech takes to reach the rear locking position depends on the position of the breech. The rear locking position of the breech may be the only position in which the breech may be secured when the firearm is cocked.